Research On Lateral Damping Device To Eliminate The Influences Of Piston Percussion

Cylinder-Piston assembly is one of important friction pairs of engine, its friction hasdirect influence on the engine power consumption, emissions and other factors. So it isnecessary to measure the friction of Cylinder-Piston assembly of engine. Compared withtraditional methods,“the floating cylinder liner method” can be more real and accurate inmeasuring friction of Cylinder-Piston assembly of engine. But the influence of cylindertransverse vibration on sensor test accuracy, which is caused by piston lateral thrust force, is akey issue that needs to be solved. So this paper utilized the finite element method to researchthe vibration attenuation impact of damping shock absorber to cylinder liner, and utilized thetests to verification.The3-D model of engine cylinder liner is established by using3-D design softwarePRO/E. Then the model is imported into finite element analysis software named ANSYS toestablish the finite element model. During the process of modeling, the simplification of thesolid model and local coordinate system is discussed, the binding modal of cylinder liner andthe influences of cylinder liner vibration under testing condition and the size of shockabsorber damping and stiffness on cylinder liner vibration amplitude is studied, recognitionprinciple of the damping of shock absorber and stiffness parameters and the design principlesand programs of shock absorber are proposed. Attenuation of shock absorber on cylinder linervibration amplitude is analyzed by using the finite element analysis software directly andtesting indirectly.The time and position of cylinder main part vibration maximum amplitude are obtainedby researching on the basic binding modes and vibration responses of cylinder liner under theexperimental conditions. The change of shock absorber damping effect is researched under experimental conditions when the shock absorber is installed in the maximum vibrationposition and its damping and stiffness change. The result shows that the damping effect isenhanced when the stiffness is unchanged and the damping increases, but as the dampingincreases, the damping effect caused by damping increasing on cylinder vibration is weakened.It also shows that damping effect is enhanced when the damping is unchanged and thestiffness increases. But the damping effect depends on the size of damping, and the greater thedamping of shock absorber is, the more damping effect is caused by same change of shockabsorber stiffness. According to the results, the principle of the shock absorber damping andstiffness parameters’ confirmation is proposed. Then a shock absorber is designed andproduced. The effect on cylinder liner vibration amplitude attenuation is verified bycomparative analysis of the amplitude change and data measured by sensor in test when thecylinder liner is in resonance.